Sex workers might be more resistant to HIV due to continued sperm exposure

In a new study, researchers have revealed that sex workers continuously exposed to semen are at low risk of getting infected with HIV. According to study authors, continued semen exposure can cause certain changes in the vaginal micro-environment that might increase resistance to the deadly HIV virus. The finding holds importance as it might help in designing a better preventive mechanism to block the virus transmission from one body to another and it will also aid in future HIV vaccine studies.

HIV prevalence is very high in some areas of the world where a high percentage of women sex workers are HIV positive. However, researchers have found that in those areas there are women in a small percentage who constantly test negative despite repeated sexual activity with rare condom use. Researchers still don’t know the reason behind such resistance towards HIV which has dumbstruck the scientists, since they seem to have none of the known immune responses against HIV itself. Linking the two — semen exposure and immunity might unravel the mystery of HIV resistance.

“Making the link between sex work, changes in immune state and semen exposure gives us an important piece of information that will hopefully help us establish whether or not chronic semen exposure and its effects on to the female reproductive tract can contribute to HIV resistance in sex workers that remain uninfected despite low condom use,” said lead author of the study Luis Montaner, professor at The Wistar Institute in Philadelphia, US.

For the study, researchers analyzed a group of sex workers in San Juan, Puerto Rico, who were tested negative for the HIV-1 virus regularly. Later, study authors compared the results with a group of women is low semen exposure, apart from comparing on rates of unprotected sex, types of contraceptives used. Researchers only took account of HIV and excluded other sexually transmitted diseases like syphilis of chlamydia.

Three different mechanisms were identified by the study authors that might lead to HIV prevention and low rate of infection among the sex workers. Moreover, the study highlights the point that increased exposure to semen can decrease infection rate while it might not remove the complete infection risk.